Forever? Maybe. But not just yet.

If it looks like a relationship, and it feels like a relationship, Sarah Millett has learned, it does not necessarily mean it's a relationship.

Millett, 26, feels battle-scarred from the ambiguous romances that have dominated her dating life, when months of regular sleepovers and daily text chats do not a boyfriend make.

"There are a lot of mixed signals," said Millett, of Denver, who has noticed she has begun protecting against potential heartache by being noncommittal herself.

Relationships have always been a reliable source of angst and anguish. But dating today has strayed so far from the structured progression most couples followed in decades past that one leading relationship researcher believes we have entered, with some peril, an "age of ambiguity."

"Ambiguity is now the norm as opposed to clarity," said Scott Stanley, co-director of the Center for Marital and Family Studies at the University of Denver and a research professor in psychology.

Ambiguity can run the gamut from friends with benefits to long-term relationships fraught with indecision about committing to a more permanent future. No study has explored whether ambiguity in romantic relationships has increased across years or generations, but the long period of relationship exploration that accompanies the rising age of marriage and the growing percentage of babies born to unmarried parents suggest commitments are fuzzier than they were a few decades back, said Galena Rhoades, an associate research professor in psychology at the University of Denver and Stanley's co-author on several studies.

Many couples claim exclusivity but won't call it a "relationship," which they fear will sour the fun with expectations, said Jessica Massa, who interviewed hundreds of singles and couples for her book, "The Gaggle: How to Find Love in the Post-Dating World" (Simon & Schuster). Others feel the term "dating" produces too much pressure and prefer to call it "hanging out."

A "perfect storm" of variables have conspired to create generation ambiguity, Stanley said.

One is cultural, he said, as the first generation of children to grow up witnessing mass divorce (now in their 20s and 30s) worry that relationships are so risky that they constantly hedge their bets.

In addition, some people who personally experienced "attachment disruptions" in childhood, often as a result of their own parents' divorce and the comings and goings of their parents' subsequent romantic partners, carry a legacy of insecurity in relationships and may cope by avoiding intimacy, feeling safer with one foot out the door, Stanley said.

As rates of marriage decline and more kids are born to unmarried parents, a trend seen mostly among lower socioeconomic classes, "I don't see how we can't be raising the greatest generation of attachment disorders in the history of our country right now," Stanley said.

Of course, plenty of kids of divorced parents don't have attachment problems and plenty of people from intact households do, as disappointments from people's own friendships and romances can leave baggage.

Shifting foundations

Brent Mattingly, assistant professor of psychology at Ursinus College in Collegeville, Pa., near Philadelphia, wonders if the rising incidence of narcissism that researchers are seeing among younger generations also could be boosting the desire for romantic ambiguity, because people primarily concerned about themselves may shun the responsibility of caring for someone else.

Massa believes discomfort with rejection among the everyone-gets-a-trophy generation is behind some of the vague intentions, facilitated by technology that lets people test the waters from behind the safety of a screen.

The most frustrating consequence of the muddle is the massive amounts of time wasted trying to psychoanalyze emoticons, Massa said. The most common question she gets on her forum is from women saying "let me tell you these 87 things that happened, and can you tell me if he likes me."

The ease of shopping online for new partners, the social acceptance of diverse romantic arrangements and the disappearance of labels like "going steady" and other public markers of relationship progression add to the dating confusion.

Ambiguity isn't bad in the early stages of relationships, when people are figuring out what they want, but it becomes tricky as the relationship wears on.

Slippery slopes

One risk of cloudy intentions is that a couple will slowly slide into living together, or having kids, or mingling finances, without explicitly choosing to do so, and then suddenly they're in a situation they can't easily escape, Stanley said.

"When you're making a commitment, you're making a choice to give up other choices," Stanley said. "When you slide, you're limiting your options, but you didn't really choose to give them up."

For some commitment-phobes, sliding into these constraints may be the only way they end up in a happy relationship they otherwise might have fled. But for others, premature entanglements prior to properly vetting the suitability of the partner leads to getting stuck in a bad relationship they didn't really want.

Another risk of chronic ambiguity is that one person feels more committed than the other but is so afraid of driving their partner away that they refrain from pushing the subject, which can cause insecurity and time spent with someone who ultimately doesn't want the same result.

"People's different expectations and assumptions about the relationship and what different things mean are what really cause a problem," said Sarah Halpern-Meekin, assistant professor in human development and family studies at the University of Wisconsin at Madison.

Ambiguous breakups also are emotionally risky, said Halpern-Meekin, who led a study, published last year in the Journal of Adolescent Research, that found more than half of young adults had sex with an ex after breaking up. Often one person hopes the inconclusiveness means the relationship is rekindling, while the other just wants to hook up until they find someone else, she said.

Yet Halpern-Meekin cautions against too much hand-wringing about ambiguity.

"I think it's important that we not mistake something like there being messiness at the beginnings and endings of relationships with the idea that there are not relationships anymore," she said.

Indeed, despite the tortured and circuitous paths they take to get there, most people do eventually want to get married, said Heidi Lyons, assistant professor of sociology at Oakland University in Rochester, Mich. Sometimes relationships that began as casual sex become meaningful ones, Lyons said.

For many young adults, ambiguity is convenient during a time in their lives when they're moving between cities or seeking temporary relationships to hold them over until they are ready to marry later in life.

Seeking structure

The greatest drawback of ambiguous relationships, Lyons said, is that they lack social scripts, so people don't know how to act, or how they should expect their partner to act, which can lead to anxiety or conflict.

The rise of online dating sites like eHarmony, which give structure to courtship, and relationship status updates on Facebook, are some ways that rules are starting to develop in the age of ambiguity.

One dating norm that may arise is clear communication upfront about what the relationship is about, Lyons said — making it, essentially, unambiguous.

Massa encourages people to embrace ambiguity in a social scene defined by the "gaggle" of will-they-or-won't-they relationships with friends and exes and the cute barista, any of whom could rise to the top with serious long-term potential.

If people focus on the connections rather than the labels, they'll be better off, she said.

"What's romantic now are these crazy confusing stories of people who couldn't stay away from each other," Massa said.

For Millett, an accumulation of disappointments has driven serious romance low on her agenda. She is enjoying traveling and being single, scared of getting involved with someone who might hold her back.

"I don't know how people do it, how people stay married for 30 years," Millett said. "I think I should just marry my gay best friend and then if we want we can have kids and lovers on the side."

In her book, "The Gaggle: How to Find Love in the Post-Dating World," author Jessica Massa defines "gaggle" as the group of guys in your life (many of whom you are not explicitly romantically involved with) who play different roles and fulfill different needs.

Her 10 examples include the ex-boyfriend who is still around, the hot sex prospect and the guy who just blew you off. Each has a link that delves a little deeper into the type, and how it can help you to "figure out who you are, what you want, and what kind of relationship you ultimately desire."